Thermal property evaluation of the multilayer bionic tree-like woven fabric by mathematic model

The thermal property of the functional bionic fabric is affected significantly by the asssembly of the yarns aggregation and the thermal property of the yarns that constructed the fabric. In this study, a thermal resistence model of the n-layer bionic fabric was proposed based on the geometrical configuration of yarns in each fabric layer. According to the Fourier law, thermal resistance equation and the effective thermal resistance equation of the n-layer bionic fabric were obtained as a function of the yarn diameter, the number of fabric layers, and the thermal conductivity of yarn. The results suggested that the aggregation of yarn in the fabric has a great effect on the thermal property of the fabric. In comparison with the control fabric, the bionic fabric with continuous yarn that constructed the tree-like structure in the thickness direction of the fabric presents a much lower thermal resistence with less than four fabric layers, and a higher thermal resistance when the number of fabric layers is greater than four. Moreover, the results revealed the analytical relationship between the bionic fabric and the thermal conductivity of yarn, the thickness of yarn, and the number of fabric layers. Experimental results agreed well with the theoretical prediction. This model provides a convenient method for thermal property prediction and optimization of the fabrics with complex configuration, and this method could equally well apply to investigate the thermal property of other woven fabrics.